/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */ 

package org.jbpm.jpdl.el.impl;

import org.jbpm.jpdl.el.ELException;

import java.math.BigInteger;
import java.math.BigDecimal;

/**
 *
 * <p>The implementation of the unary minus operator
 * 
 * @author Nathan Abramson - Art Technology Group
 * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author$
 **/

public class UnaryMinusOperator
  extends UnaryOperator
{
  //-------------------------------------
  // Singleton
  //-------------------------------------

  public static final UnaryMinusOperator SINGLETON =
    new UnaryMinusOperator ();

  //-------------------------------------
  /**
   *
   * Constructor
   **/
  public UnaryMinusOperator ()
  {
  }

  //-------------------------------------
  // Expression methods
  //-------------------------------------
  /**
   *
   * Returns the symbol representing the operator
   **/
  public String getOperatorSymbol ()
  {
    return "-";
  }

  //-------------------------------------
  /**
   *
   * Applies the operator to the given value
   **/
  public Object apply (Object pValue,
		       Logger pLogger)
    throws ELException
  {
    if (pValue == null) {
      /*
      if (pLogger.isLoggingWarning ()) {
	pLogger.logWarning
	  (Constants.ARITH_OP_NULL,
	   getOperatorSymbol ());
      }
      */
      return PrimitiveObjects.getInteger (0);
    }

    else if (pValue instanceof BigInteger) {
        return ((BigInteger) pValue).negate();
    }

    else if (pValue instanceof BigDecimal) {
        return ((BigDecimal) pValue).negate();
    }

    else if (pValue instanceof String) {
      if (Coercions.isFloatingPointString (pValue)) {
	double dval =
	  ((Number) 
	   (Coercions.coerceToPrimitiveNumber 
	    (pValue, Double.class, pLogger))).
	  doubleValue ();
	return PrimitiveObjects.getDouble (-dval);
      }
      else {
	long lval =
	  ((Number) 
	   (Coercions.coerceToPrimitiveNumber 
	    (pValue, Long.class, pLogger))).
	  longValue ();
	return PrimitiveObjects.getLong (-lval);
      }
    }

    else if (pValue instanceof Byte) {
      return PrimitiveObjects.getByte 
	((byte) -(((Byte) pValue).byteValue ()));
    }
    else if (pValue instanceof Short) {
      return PrimitiveObjects.getShort 
	((short) -(((Short) pValue).shortValue ()));
    }
    else if (pValue instanceof Integer) {
      return PrimitiveObjects.getInteger 
	((int) -(((Integer) pValue).intValue ()));
    }
    else if (pValue instanceof Long) {
      return PrimitiveObjects.getLong 
	((long) -(((Long) pValue).longValue ()));
    }
    else if (pValue instanceof Float) {
      return PrimitiveObjects.getFloat 
	((float) -(((Float) pValue).floatValue ()));
    }
    else if (pValue instanceof Double) {
      return PrimitiveObjects.getDouble 
	((double) -(((Double) pValue).doubleValue ()));
    }

    else {
      if (pLogger.isLoggingError ()) {
	pLogger.logError
	  (Constants.UNARY_OP_BAD_TYPE,
	   getOperatorSymbol (),
	   pValue.getClass ().getName ());
      }
      return PrimitiveObjects.getInteger (0);
    }
  }

  //-------------------------------------
}
